/*
 * Copyright 2012-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.boot.convert;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 声明字段或方法参数在转换为集合时应使用指定的分隔符。
 *
 * @author Phillip Webb
 * @since 2.0.0
 */
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD, ElementType.FIELD, ElementType.PARAMETER, ElementType.ANNOTATION_TYPE })
public @interface Delimiter {

	/**
	 * 一个特殊的分隔符值，表示不使用分隔符，结果应为包含整个字符串的单个元素。
	 */
	String NONE = "";

	/**
	 * 要使用的分隔符；如果应将整个内容视为单个元素，则为 {@code NONE}。
	 * @return 分隔符
	 */
	String value();

}
